The United States and Japan will step up their defence cooperation to deal with the threat from nuclear-armed North Korea as tensions in East Asia remain high, officials from the two allies said on Thursday.

PM Turnbull pays tribute to Helmut Kohl

Malcolm Turnbull has paid tribute to Helmut Kohl's efforts to shape modern Europe following the former German chancellor's death.

He was the driving force behind a common European currency, cemented Germany's partnership with France, and would always be remembered for promoting global peace and prosperity, the prime minister said.

"Chancellor Kohl was also a good friend to Australia and was committed to the partnership between Australia and Germany which continues to go from strength to strength," Mr Turnbull said on Saturday.